1. Field of the Invention
The invention relates to a connector for an electric or electronic device, in particular to a circuit board connector, to a terminal fitting therefor, to chained terminals and to a method of mounting a connector to an electric or electronic device such as a printed circuit board.
2. Description of the Related Art
U.S. Pat. No. 6,354,871 discloses a circuit board connector that comprises a housing to be fixed to a circuit board and terminal fittings that are pressed into the housing. A terminal connecting portion is defined at one end of each terminal fitting and projects into the housing for electrical connection with a mating terminal. A board connecting portion is defined at the opposite end of each terminal fitting and is drawn out of the housing for soldered connection with a conductor on the outer surface of the circuit board.
Solder adhered to parts of the board connecting portions forward of the rear end surfaces generally are hidden by the adjacent terminal fittings and/or by the housing. As a result, the adequacy of the solder connection of the board connecting portions typically is tested visually by looking at the height of solder adhered to the extending rear end surfaces of the board connecting portions.
Plating, such as tin plating, is applied to the outer surfaces of the terminal fittings to improve contact reliability of the terminal connecting portions with the mating terminal fittings. Plating also improves the affinity of solder at the board connecting portions to enable satisfactory soldering.
FIG. 7(A) shows terminal fittings produced by punching an electrically conductive metal sheet to obtain chained terminals 1. The chained terminals 1 have a long carrier 3 and terminal fittings 4 project side by side from one lateral edge of the carrier 3. Couplings 5 join the terminal fittings 4 to the carrier 3, and board connecting portions 6 are adjacent to the couplings 5. Rear end surfaces of the board connecting portions 6 define the solder testing areas and are exposed. The plating applied to the chained terminals 1 desirably forms metal films on the exposed solder testing surfaces at rear ends of the board connecting portions 6, and hence makes the solder test more reliable.
The couplings 5 must be between the board connecting portions 6 of the above-described chained terminals 1, and accordingly intervals between the terminal fittings 4 is wide. An attempt could be made to narrow the intervals between the terminal fittings 4, as shown in FIG. 7(B). However, this requires narrower and weaker couplings 5 that can be difficult to press work. As a result, intervals between the terminal fittings 4 are not narrowed easily, thereby complicating further miniaturization and leading to a higher cost.
Moreover, solder applied to the conductors adheres only to lower surfaces and opposite side surfaces of the board connecting portions of the above-described terminal fittings. Thus, forces on the board connecting portions in a direction away from the circuit board can detach the board connecting portions from the conductors, thereby impairing connection reliability.
The present invention was developed in view of the above problems, and an object thereof is to improve overall operability of a connector to be mounted to an electric or electronic device such as a printed circuit board.